Repetitive Magnetic Stimulation Limits Migraine Frequency, Study Finds

Sessions of repetitive peripheral magnetic stimulation (rPMS) applied to patients with high-frequency episodic migraine significantly decreased frequency of headache days, according to a study published in Scientific Reports.

The study included 37 patients with migraine who all presented at least 1 active myofascial trigger point (mTrP) in the trapezius muscles and 1 latent mTrP in the deltoid muscles. Average participant age was 25 years and 36 of the 37 patients were female.

Researchers randomly selected patients to receive rPMS to the mTrPs of the trapezius (n = 19) or deltoid (n = 18) muscles. In total, patients underwent 6 sessions of rPMS over 2 weeks. Participants also completed the Migraine Disability Assessment (MIDAS) questionnaire prior to and after intervention was completed.

“RPMS offers a...non-invasive neuromodulatory approach that can directly intervene at peripheral muscular structures in the neck and shoulder area whilst potentially using the trigeminocervical complex (TCC) as a gateway to modulate central nociception simultaneously,” researchers said. “According to the concept of the TCC, peripheral sensitization and central convergence of cervical and meningeal nociceptive afferents in the brain stem could explain the important correlation of neck pain and migraine.”

Intervention included stimulation of both the left and right mTrPs of the trapezius muscles or the left and right mTrPs of the deltoid muscles. Each side was stimulated for 15 minutes, and 1 session consisted of 20 bursts at a 20-Hz frequency.

Because the trapezius muscle is part of the TCC and might be involved in the pathophysiology of migraine, researchers included stimulation of the deltoid muscle as a control. However, data show the treatment was effective in both cohorts.

In particular, “headache frequency per 90 days significantly decreased in the trapezius group from 23 to 16 days (P = .005, relative reduction −34.8%) and in the deltoid group from 20 to 14 days (P = .003, relative reduction −32.5%).” The cumulative duration of headache attacks also decreased (trapezius group: P = .068, relative reduction, −23.2%; deltoid group: P = .076, relative reduction, −37.2%).

Additional findings include:

• MIDAS score decreased from 29 to 13 points (P = .0004) in the trapezius group and from 31 to 15 points in the deltoid group (P = .002)
• Median MIDAS score changed from “severe impairment” to “moderate impairment” in both groups (trapezius group: P = .0005; deltoid group: P = .009)
• MIDAS score improved significantly after rPMS (P = .001)
• Productivity at school/work was less affected by headache events after treatment than prior to intervention (trapezius group: P = .001, relative reduction, −40.0%; deltoid group: P = .005, relative reduction, −53.3%)

“The positive central effect after stimulation of the deltoid muscle might be explained by the uplifting movement of the shoulder, which is provoked by rPMS on the deltoid muscle and which might indirectly active the trapezius muscle,” researchers note.

They warn the placebo effect may have distorted patients’ self-reported findings and sham-controlled trials ought to be conducted in the future.

Reference

Renner T, Sollmann N, Heinen F, et al. Alleviation of migraine symptoms by application of repetitive peripheral magnetic stimulation to myofascial trigger points of neck and shoulder muscles — a randomized trial [published online April 6, 2020]. Sci Rep. doi: 10.1038/s41598-020-62701-9.